Visual Testing in Petrochemical: What It Finds, What It Misses, and What Governs It
What VT is actually used for in petrochemical
Visual examination governs petrochemical turnaround scope — refractory condition, tray and internals damage, and coating breakdown are all visual calls that steer the volumetric work.
How VT works
Visual testing is the examination every other method is deployed against: direct or remote observation under controlled lighting and access, judged against written acceptance criteria. It finds the majority of reportable conditions in most programmes — weld profile, corrosion, mechanical damage, coating breakdown, leakage evidence — and it decides where volumetric examination is worth performing.
What VT will not do
What VT will not do: see beneath the surface, quantify wall loss, or substitute for a volumetric method where the code requires one. Its weakness is human rather than physical — inconsistent lighting, inadequate access, and acceptance criteria applied from memory rather than from the document.
The petrochemical assets this applies to
Crackers and their furnaces, polymer trains, reactors and columns, compressor stations, and the utilities and storage that support them.
The damage mechanisms driving the examination
High-temperature degradation dominates — creep and carburisation in furnace tubing, thermal fatigue at cyclic services — alongside chloride stress corrosion cracking in austenitic systems and erosion in catalyst-handling circuits.
What governs acceptance
API in-service codes with ASME construction acceptance, plus process-specific licensor requirements that frequently exceed the code minimum on critical equipment. On the method side: ASME Section V Article 9; AWS D1.1 for structural acceptance; API 510/570/653 for in-service external and internal examination; ASME B31.3 for process piping. An examination that is technically sound but performed outside the governing regime is not an examination anyone will accept, which is why the code family matters as much as the technique.
How Atlantis delivers VT in this sector
Atlantis mobilises examination teams to your site under Atlantis procedures with ASNT Level III oversight — we do not claim a depot or laboratory in every market, and say so plainly. What you receive is the examination performed to a qualified procedure, findings evaluated against the acceptance criteria your contract names, and records structured to survive a client audit years later.
Visual Testing services · VT training and certification · Petrochemical programme consulting · Petrochemical NDT training · scope a VT examination.
VT in other sectors
Refining · LNG · Offshore · Pipeline · Marine & Shipbuilding · Aviation & Aerospace.